Question

Match each description to a type of evolutionary evidence in the key. Key: a. biogeography b. fossil record c. comparative biochemistry d. comparative anatomy The same types of molecules are found in all living things.

Short answer

The correct match for the description is c. comparative biochemistry, as it indicates the presence of the same types of molecules in all living things.

Step-by-step solution

Identify the evolutionary evidence in the description

According to the description, the same types of molecules are found in all living things. This statement suggests that there is a commonality among all living organisms in terms of their molecular structure.

Match the description to the key

From the given key, the description best matches with the evolutionary evidence of comparative biochemistry (option c), as it focuses on the similarities in the molecular structure and chemical processes among different organisms as evidence for evolution. So, the correct answer is: c. comparative biochemistry

Key concepts

Biogeography

Biogeography is the scientific study of the geographical distribution of living organisms. From the perspective of evolution, biogeography provides evidence in the form of distinct patterns that organisms show across different regions and ecosystems. For example, islands often have species that are related to those on the nearest continent but have become distinct due to evolutionary processes in isolation.

This isolation can lead to speciation, where new species evolve from a common ancestor when populations are separated by geographic barriers. Such patterns where related species are found in close but distinct areas point towards evolution through natural selection and adaptation to different environments. Islands like the Galápagos, with their unique species of finches, stand as classic examples that Charles Darwin himself observed.

Fossil Record

The fossil record is a collection of fossils that have been discovered and catalogued. It provides chronological evidence of species evolving over time. Through the careful examination of the fossil record, scientists can trace the gradual changes that have taken place in the morphology and size of organisms, which demonstrates the concept of descent with modification.

For instance, the transition from land-dwelling mammals to whales is well documented by a series of intermediate fossils with features of both land mammals and modern whales. These transitional fossils are powerful evidence that helps us understand how species can give rise to new species over millions of years, a process known as speciation.

Comparative Biochemistry

Comparative biochemistry looks at the molecular level to find similarities and differences in the biochemical processes and substances within living organisms. The presence of the same types of molecules and similar genetic code among vastly different species suggests a common ancestry.

For example, cytochrome c is a protein that is critical in the energy-producing structures of cells. It is remarkably similar across various species, from yeasts and plants to insects and humans, indicating that these diverse forms of life share a distant common ancestor. Comparative biochemistry also studies enzymes, DNA sequences, and metabolic pathways to trace evolutionary relationships.

Comparative Anatomy

Comparative anatomy investigates the similarities and differences in the anatomical structures of different species. Homologous structures, which are body parts that are similar in structure but may function differently in different species, provide strong evidence of common descent.

An instance of homologous structures is the forelimbs of humans, cats, whales, and bats. Despite different functions – grabbing, walking, swimming, and flying, respectively – these limbs have a comparable bone structure that indicates a shared evolutionary origin. On the other hand, analogous structures, such as the wings of birds and insects, serve similar functions but have evolved independently. Analyzing these similarities and differences deepens our understanding of evolutionary processes.